Pollutant Concentrations

Air quality readings will be available hourly from 7am to 11pm. Air quality readings from 12am to 6am will be made available at 7am on the same day.

Readings on 18 Nov 2014

View reading for:

Region

24-hr Sulphur dioxide(µg/m3)

24-hr PM10(µg/m3)

1-hr Nitrogen dioxide(µg/m3)a

8-hr Ozone(µg/m3)

8-hr Carbon monoxide(mg/m3)

24-hr PM2.5(µg/m3)

North

5(3)

22(22)

37(-)

7(3)

0.4(4)

11(46)

South

7(4)

19(19)

41(-)

4(2)

0.6(6)

10(43)

East

3(2)

17(17)

19(-)

9(4)

0.5(5)

11(46)

West

3(2)

23(23)

32(-)

12(5)

0.5(5)

12(49)

Central

9(5)

19(19)

43(-)

14(6)

0.7(7)

10(42)

1-hr PM2.5 (µg/m3)b Readings on 18 Nov 2014

View reading for:

Time

1am

2am

3am

4am

5am

6am

7am

8am

9am

10am

11am

12pm

North

3

14

10

14

14

9

8

14

12

16

20

15

South

3

8

4

8

8

7

8

10

14

14

19

15

East

11

16

10

16

16

14

13

13

12

15

27

24

West

6

6

8

6

6

5

5

6

4

7

14

12

Central

6

12

8

12

12

16

8

15

13

16

12

12

Time

1pm

2pm

3pm

4pm

5pm

6pm

7pm

8pm

9pm

10pm

11pm

12am

North

13

8

3

4

7

12

15

12

13

12

18

-

South

20

19

6

10

9

9

10

13

10

13

9

-

East

17

7

3

5

5

5

7

7

8

11

6

-

West

21

20

17

12

18

6

17

22

27

12

15

-

Central

13

10

5

10

9

6

9

14

8

10

11

-

Note:a Sub-index for nitrogen dioxide is reported only when the 1-hr concentration equals or exceeds 1130 µg/m3.

b There is no sub-index for 1-hr PM2.5.

3-hr PSI Readings from 1am to 12am on
18 Nov 2014

Time

1am

2am

3am

4am

5am

6am

7am

8am

9am

10am

11am

12pm

3-hr PSI

30

31

31

37

41

44

42

42

43

51

53

55

Time

1pm

2pm

3pm

4pm

5pm

6pm

7pm

8pm

9pm

10pm

11pm

12am

3-hr PSI

56

53

47

38

34

35

40

46

52

52

51

-

Hourly updates of 3-hr PSI readings are provided from 7am to 11pm. The 3-hr PSI readings from 12am to 6am will be made available at 7am on the same day. The 3-hr PSI readings are calculated based on PM2.5 concentrations only.